A heat exchanger is an apparatus which transfers part of the heat of a hot fluid to a cold fluid, and is also called heat exchanging apparatus. The heat exchanger is widely used in the fields of HVAC (Heating, Ventilation, and Air Conditioning) and the like.
Please refer to FIG. 1, which is a schematic structural view of a heat exchanger in the prior art.
Currently, a typical heat exchanger 10 generally includes two manifolds 101 (only one manifold 101 at a side of the heat exchanger is shown in FIG. 1) arranged parallel to each other. Multiple heat exchanging tubes 102 are arranged substantially parallel to each other between the manifolds 101. Radiating fins are arranged at intervals between the heat exchanging tubes 102. The heat exchanging tube 102 has two ends communicating with the manifolds 101 at two sides of the heat exchanging tube. The refrigerant enters the heat exchanging tubes 102 through a manifold 101 at one side of the heat exchanger, thereby accomplishing heat exchanging.
In order to ensure that the refrigerant in the heat exchanger 10 is distributed in the heat exchanging tubes 102 evenly, generally a refrigerant guide tube 103 is inserted into each of the manifolds 101. The guide tube 103 is inserted into the bottom portion of each of the manifolds 101, and openings 1031 are arranged along the guide tube 103 and spaced at a certain interval. The ends of the guide tube 103 are sealed, and each opening 1031 in the guide tube 103 is responsible for distributing or collecting the refrigerant in the heat exchanging tube 102 in a corresponding area, so that the refrigerant can be distributed evenly through these openings 1031 into the respective heat exchanging tubes 102 to be recirculated, or, the refrigerant flowing out of the heat exchanging tubes 102 can be collected evenly into the guide tube 103 and then flow out of the heat exchanger. That is, the openings 1031 serve as passages for the refrigerant to flow into or out of the guide tube.
To manufacture the guide tube 103 with the openings 1031 as refrigerant passages, conventionally, the surface of the tube body of the guide tube 103 is directly processed and punched. In the case of a microchannel heat exchanger, the internal diameter of the guide tube 103 is relatively small. When functioning as a distribution tube, the diameter of the guide tube 103 is even smaller, around 10 mm. Therefore, it is technically difficult, not efficient, and costly to manufacture openings 1031 directly on the arc surface of the tube body of the guide tube 103. Furthermore, metal burrs and metal shavings and the like may be left on the inner side of the openings 1031 of the tube body. Since the diameter of the tube is small, the metal burrs and metal shavings inside the tube are difficulty removed, which may block the openings 1031 in operation of the system, and cause the refrigerant to be distributed unevenly. In some cases, the free metal shavings may even block the throttle mechanism and cause system failure.
Therefore, there is an urgent demand in the art to facilitate the manufacture of the openings on the refrigerant guide tube and remove the burrs and shavings on the inner side of the openings of the tube body.